package com.mapflow.util;

import org.apache.commons.beanutils.ConversionException;
import org.apache.commons.beanutils.Converter;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import java.text.DecimalFormat;
import java.text.ParseException;

/**
 * This class is converts a Double to a double-digit String (and vise-versa) by BeanUtils when
 * copying properties.
 * 
 * @author <a href="mailto:matt@raibledesigns.com">Matt Raible</a>
 */
public class CurrencyConverter implements Converter {

  private final Log log = LogFactory.getLog(CurrencyConverter.class);
  private DecimalFormat formatter = new DecimalFormat("###,###.00");

  public void setDecimalFormatter(DecimalFormat df) {
    this.formatter = df;
  }

  /**
   * Convert a String to a Double and a Double to a String
   * 
   * @param type
   *          the class type to output
   * @param value
   *          the object to convert
   * @return object the converted object (Double or String)
   */
  @SuppressWarnings("rawtypes")
  public final Object convert(final Class type, final Object value) {
    // for a null value, return null
    if (value == null) {
      return null;
    }
    else {
      if (value instanceof String) {
        if (log.isDebugEnabled()) {
          log.debug("value (" + value + ") instance of String");
        }

        try {
          if (StringUtils.isBlank(String.valueOf(value))) {
            return null;
          }

          if (log.isDebugEnabled()) {
            log.debug("converting '" + value + "' to a decimal");
          }

          // formatter.setDecimalSeparatorAlwaysShown(true);
          Number num = formatter.parse(String.valueOf(value));

          return num.doubleValue();
        }
        catch (ParseException pe) {
          pe.printStackTrace();
        }
      }
      else if (value instanceof Double) {
        if (log.isDebugEnabled()) {
          log.debug("value (" + value + ") instance of Double");
          log.debug("returning double: " + formatter.format(value));
        }

        return formatter.format(value);
      }
    }

    throw new ConversionException("Could not convert " + value + " to " + type.getName() + "!");
  }
}
